The present invention relates to an elevator installation with a modular drive and to a method for converting an elevator installation.
An elevator installation serves the purpose of transport of persons and goods within a building between floors. A car serves for reception of the persons and goods. A drive drives the car by means of a support means, the car thereby being moved back and forth in a vertically extending shaft. The support means connects the car with a counterweight. It is in that case guided by way of a drive pulley. The drive pulley transmits to the support means the force required for moving or stopping. The drive pulley is for that purpose driven or stopped by a drive device and/or a brake device.
Another type of drive drives the car by means of hydraulic elevatoring apparatus. The driving and stopping force is in that case transmitted to the car by a pump unit acting directly by way of a piston or acting indirectly by means of a cable or chain pull.
Both types of drive have specific use characteristics and in addition they are subject to wear. The use characteristics are, for example, the travel speed or the carry load for which the elevator installation is designed. Wear arises due to, for example, long-term utilization of the elevator installation which leads to wear phenomena at components of the elevator installation. If the use requirements change or if the wear is too great the drive, or if need be the entire elevator, has to be replaced or renewed.
In order to cover a widest possible field of use in the case of replacement of existing elevator drives or entire elevator installations with few components, universally or modularly usable drive engines are required.
Drives which are small and compact or enable variable support means take-offs are known. Thus, European patent specification EP 0 763 495 shows a drive engine which produces a change in the support means spacing (a) by changing the installation slope. The spacing between the support means run running up to the drive engine and the support means run running down is termed support means spacing. The illustrated drive engine has the disadvantage that it is fit to an engine space with specially made support pedestals and accordingly is not suitable for installation in an existing engine space or in a shaft, a change in the support means spacing (a) produces a change in the looping angle (β) and the unit is large, which has a disadvantageous effect in the case of installation in an existing building. The looping angle (β) denotes the angle by which the support means loop the drive pulley. The force transmissible from the drive pulley to the support means is usually dependent on the looping angle (β).
A drive engine which is of compact construction and can be mounted within the shaft space is shown in PCT specification WO 01/28911. The drive engine has a fixed support means spacing. The disadvantage of this solution is the lack of flexibility of the drive, since it does not allow any adjustment of the support means spacing.